Functional and Structural Analysis of the 18S rRNA aminocarboxypropyl transferase Bam1

18S rRNA氨基羧丙基转移酶Bam1的功能和结构分析

• 批准号: 277406224
• 负责人: Professor Dr. Karl-Dieter Entian
• 金额: --
• 依托单位: Institut für Molekulare Biowissenschaften
• 依托单位国家: 德国
• 项目类别: Priority Programmes
• 财政年份: 2015
• 资助国家: 德国
• 起止时间: 2014-12-31 至 2019-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/277406224?language=en
• 关键词: Functional; Structural; Analysis; 18S; rRNA

N1-methyl-N3-aminocarboxypropyl-pseudouridine is the chemically most complex modification occurring in eukaryotic small ribosomal subunit rRNA. Its biosynthesis from uridine requires three steps. The uridine to pseudouridine modification is catalyzed by a snoRNP guided by snR35. We previously showed that the SPOUT-class methyltransferase Nep1 introduces the N1-methyl group. Very recently we identified the enzyme that transfers the acp group to the N1-methylpseudouridine which we named Bam1. Here we propose to establish the structural and functional basis for the acp transferase activity of Bam1 and in particular to understand the structural prerequisites that allow Bam1 to utilize SAM as a substrate for acp transfer instead as a methyl group donor. Furthermore, we aim at understanding the catalytic mechanism of this reaction. The availability of knock-out and mutant strains for Bam1 in yeast will allow us to investigate the physiological relevance of this chemically complex modification and its importance in ribosome biogenesis. Due to the strong human homologies, our investigation could possibly also unravel new ribosomopathies, similar to the Bowen-Conradi syndrome observed for Nep1 catalysed N1-methylation.

N1-甲基-N3-氨基羧基丙酰丙啶是在真核小型核糖体亚基RRNA中发生的化学最复杂的修饰。它的生物合成需要三个步骤。 SNR35引导的snornp催化了尿苷至伪氨酸修饰。我们先前表明，喷口级甲基转移酶NEP1引入了N1-甲基。最近，我们确定了将ACP组转移到我们命名为BAM1的N1-甲基甲基苯胺氨酸的酶。在这里，我们建议建立BAM1的ACP转移酶活性的结构和功能基础，尤其是了解允许BAM1用作ACP转移的底物的结构先决条件，而是作为甲基供体。此外，我们旨在理解该反应的催化机制。 BAM1在酵母中的敲除和突变菌株的可用性将使我们能够研究这种化学复杂修饰的生理相关性及其在核糖体生物发生中的重要性。由于人类的同源性很强，我们的研究也可能揭示新的核糖体病，类似于观察到的NEP1催化N1-甲基化的Bowen-Conradi综合征。